Errors Involving Medications Common In Outpatient Cancer Treatment

January 1, 2009 — Seven percent of adults and
19 percent of children taking chemotherapy drugs in outpatient clinics
or at home were given the wrong dose or experienced other mistakes
involving their medications, according to a new study led by Kathleen
E. Walsh, MD, assistant professor of pediatrics at the University of
Massachusetts Medical School.

"As cancer care continues to shift from the hospital to the
outpatient setting, the complexity of care is increasing, as is the
potential for medication errors, particularly in the outpatient and
home settings," said Dr. Walsh, who is also a Robert Wood Johnson
Physician Faculty Scholar.

An analysis of data on nearly 1,300 patient visits at three adult
oncology outpatient clinics and 117 visits at one pediatric facility
between September 1, 2005 and May 31, 2006 showed that errors in
medication were more common than previously reported by oncology
patients.

Of the 90 medication errors involving adults, 55 had the potential
to harm the patient and 11 did cause harm. The errors included
administration of incorrect medication doses due to confusion

over conflicting orders – one written at the time of diagnosis and
the other on the day of administration. Patients were also harmed by
over-hydration prior to administration of medication, resulting in
pulmonary edema and recurrent complaints of abdominal pain and
constipation. More than 50 percent of errors involving adults were in
clinic administration, 28 percent in ordering of medications, and 7
percent in use of the drugs in patients' homes.

About 40 percent of the 22 medication errors in children had the
potential to cause harm and four children were harmed. More than 70
percent of the errors in children occurred at home. Examples of
pediatric errors included parents giving the wrong dose or the wrong
number of doses per day of medicines because of a caregiver's confusion
about instructions.

"Requiring that medication orders be written on the day of
administration, following review of lab results, may be a simple
strategy for preventing errors among adults, while most of the errors
involving children may have been avoided by better communication and
support for parents of children who use chemotherapy medications at
home," said Dr. Walsh.

The study was supported in part by the US Health and Human Services
Agency for Healthcare Research and Quality through its Centers for
Education and Research on Therapeutics program.